Hi, I discovered a strange problem with my fonts the other day and I'd like to know if anybody here encountered sth like this too.

On my PC I have Windows 10 – the upgraded version (what a mistake to do this ...). A few days ago it wanted an update, and afterwards several of my fonts didn't work anymore.
I have lots of old fonts on my PC, mostly TTF, but also some Type1 fonts. I never had any problems. But now strange things are going on. In Word for instance, some fonts aren't even shown in the font list anymore, like they're no longer installed. Yet when I try to re-install them I get the message that they are already installed. However, they don't show in the installed fonts folder of the system control, and even when I select to replace them, they still won't.
Other fonts do show in the font list of a program, but when I select them, the text will display in some other font and in the font list the font name will now say "Can't be found".
Some of these buggy fonts can be re-installed by using Bitstream FontNavigator (which comes with Corel Draw), namely those that I can't re-install the usual way because I'll get the message that they already are installed.
But I haven't found a solution yet for those that are shown in the font list of programs but don't display correctly. In FontNavigator those are shown like they are installed, but the preview window is empty.

I ran a system restore which restored some of the fonts, but not all. I guess some must have been buggy before this last update. But of course Windows 10 will want to do the update again, so I'll need to find a way to fix this. Some of these corrupted fonts I really need and they are not substitutable.
So if anyone heard about problems like this before I'd appreciate your opinions!

I've been googling a lot about this and I have also found out by now that the Creator's update is the reason for this.
People on various forums said that their fonts work every other time they boot their computer, so every day they have to boot twice in order to make them work.
For me that wasn't true. They did work occasionally, but more often than not they didn't.
BUT just the other day there was another update and since then the fonts work for the most part. The strange thing is, they didn't right away after the update. First couple times or so I booted they didn't work. Then one time they did and the past few days they were okay too. I'll have to wait and see though if this is consistent now.